OK, let's do this. We've got 9552 and 5944 and we're adding them all together.

Step 1: We'll start by adding the digits 2 & 4 in column 1 and get 6.

Step 2: We'll start by adding the digits 5 & 4 in column 2 and get 9.

Step 3: We'll start by adding the digits 5 & 9 in column 3 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 5 in column 4 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

So, 9552 + 5944 = 15496.

